In search of cancer chemotherapeutic agents for metastatic neuroblastoma, we found bromoacetylcholine to be a hopeful one because we found it inhibits neuroblastoma irreversibly at 1 x 10 to the minus 5th power M and induces cytolysis at 2 x 10 to the minus 5th power M or higher. It is therefore proposed to study the following with bromoacetylcholine: 1. Determination of ED50 and ED99 of bromoacetylcholine to inhibit neuroblastoma in vivo and LD50 and LD1 to kill mice. From this information, therapeutic index (LD50/ED50) and certain safety factors (LD1/ED99) will be calculated. The ID50 of bromoacetylcholine to inhibit neuroblastoma in vitro will also be determined. 2. Investigation of action mechanism of bromoacetylcholine to inhibit neuroblastoma: (a) Is the inhibition of neuroblastoma by bromoacetylcholine due to the binding of bromoacetylcholine to the nicotinic receptor? (b) How many binding sites are there in neuroblastoma cells? (c) Is the inhibition caused by the hydrolyzed product of bromoacetylcholine, bromoacetate? 3. Prevention of muscarinic side effects by using muscarinic blocking agents along with bromoacetylcholine. These blocking agents alone will also be tested to see whether the cell growth will be affected by these agents. 4. Determination of best ways by which bromoacetylcholine can be administered to the animal, including the timing and routes of administration.